PDT With Metvix 160 mg/g Cream Versus PDT With Placebo Cream in Participants With Primary Nodular Basal Call Carcinoma

A Multicentre, Phase III, Double Blind Study of Photodynamic Therapy (PDT) With Metvix® 160 mg/g Cream in Comparison to PDT With Placebo Cream in Participants With Primary Nodular Basal Cell Carcinoma

Photodynamic therapy (PDT) was the selective destruction of abnormal cells through light activation of a photosensitiser in the presence of oxygen. These cells accumulated more photosensitiser than normal cells. The photosensitiser generated reactive oxygen species upon illumination.

For skin diseases, there had been an increasing interest in using precursors of the endogenous photosensitiser protoporphyrin IX (PpIX). The most commonly used precursors had been 5-aminolevulinic acid (ALA) and its derivatives. The present test drug, Metvix®, contained the methyl ester of ALA, which penetrated the lesions well and shows high lesion selectivity .

In vitro studies of animal and human tissues had shown significant intracellular formation of photoactive porphyrins after addition of Metvix®. The increased levels of photoactive porphyrins induced cytotoxic effects in tumour cells after photoactivation.

The primary objective was to compare PDT with Metvix® cream to PDT with placebo cream in terms of participant complete response rates based on histologically verified disappearance of the lesions at 6 months after last treatment cycle.

Secondary objectives were to compare the two treatments in terms of histological and clinical mean participant response weighted by the number of lesions within a participant, lesion response rates across participants, clinical complete participant response, cosmetic outcome and adverse events.

A participant was randomised to PDT with Metvix® cream or PDT with placebo cream. All eligible Basal cell carcinoma (BCC) lesions within a participant had got the same treatment. All participants got two consecutive treatments one week apart. At the 3-months follow-up visit, lesions with no clinical response or progression had been surgically excised. Lesions with partial response (50% or greater reduction on lesion area) had been re-treated, if they do not show complete response three months later they would have been be surgically excised. Lesions with complete response had been surgically excised 6 months after the first or second PDT cycle. All excised tissue specimens had been histologically examined.

Inclusion Criteria:

A participant with primary, nodular BCC lesion(s) suitable for entry is defined as a participant with

• Clinically diagnosed primary nodular BCC lesion(s).
• Histologically confirmed diagnosis of BCC.
• BCC lesions suitable for simple excision surgery.
• Males or females above 18 years of age.
• Written informed consent.

Exclusion Criteria:

A participant that is ineligible for inclusion is a participant fulfilling any of the following criteria:

• Participants with porphyria.
• Participant with Gorlin's syndrome.
• Participant with Xeroderma pigmentosum.
• Participants concurrently receiving immunosuppressive medication.
• Participants with a history of arsenic exposure.
• Known allergy to Metvix®, a similar PDT compound or excipients of the cream.
• Participation in other clinical studies either concurrently or within the last 30 days.
• Pregnant or breast-feeding: All women of child-bearing potential must use adequate contraception (e.g. barrier methods, oral contraceptives or intrauterine device) during the treatment period and one month thereafter. In addition, they must have a negative pregnancy test prior to treatment.
• Conditions associated with a risk of poor protocol compliance.

Lesion Exclusion Criteria:

• A nodular BCC lesion in periorbital area, ears and nasolabial fold.
• A nodular BCC lesion with the longest diameter less than 6 mm or larger than 15 mm in face/scalp, larger than 20 mm on extremities and neck and larger than 30 mm on truncus.
• Pigmented nodular BCC lesion(s).
• Morpheaform nodular BCC lesion(s).
• Infiltrating nodular BCC lesion(s).
• Prior treatment of the BCC lesion(s).